Instrument for setting position of a tool for the grinding thereof



March 27, 1945. I w J, CLEM NTS 2,372,552

INSTRUMENT FOR SETTING POSITION OF A TOOL FOR THE GRINDING THEREOF Filed Dec. '5, 1942 INVENTOR 14 44/220 J. 6.46245):

ATTORNEY-1 angles thereto.

Patented Mar. 27, 1945 UNITED INSTRUMENT FOR SETTING POSITION OF A TOOL FOR THE GRINDING THEREOF Willard J. Clements, Milwaukee, Wis., assignor to Wetmore Reamer Company, Milwaukee, Wis'., a corporation of Wisconsin Application December 5, 1942, Serial No. 468,012

12 Claims. (Cl. 51-220) This invention relates to an instrument for setting the position of a tool for the grinding thereof.

Cutting tools, such as those used in boring bars and the like, have to be ground to provide both side rake and back rake. The mounting of the tool in a universal vise for the proper presentation of its face to a grinding wheel has heretofore been a matter requiring a very considerable expenditure of time. On the average, from one half hour to several hours has been spent in positioning a single tool for grinding because of the fact that when the angularity of the surface to be ground is adjusted in one plane, the adjustment upsetsan adjustment previously made in a plane at right The present invention seeks to provide means whereby the exact angularity in each of the two planes in which side and back rake is provided may be determined concurrently. thereby reducing to approximately two minutes the time required to position the tool in a fixture for grinding. I The problem is complicated by the fact that different tools are inserted at different angles in their respective boring bars or other supports in which the tools are used. These angles must be allowed for in positioning the tool for grinding,

inasmuch as the tool, for convenience, is usually setat right angles to the path of the grinder. It is an object of the invention to provide novel'and simple means readily adjustable to determine any desired angles of back and side rake in any desired planes, while allowing for any desired ani the respective arms are pivotally adjustable is itself rotatably adjustable about a third axis normal to the axes upon which the respective arms are movable.

The objectand advantages of the invention will be more apparent to those skilled in the art upon analysis of the following disclosure thereof.

In the drawing: Fig. 1 is a view in perspective per se. I

Fig. 2 is a view in side elevation of the instruof the instrument ment in use upon a fixture set up in a universal vise on the table of a surface grinder.

Fig. 3 is a view in end elevation of the tool as it appears in the fixture.

Fig. 4 is a view in side elevation of the tool as it appears in the fixture, the latter being fragmentarily illustrated.

Fig. 5 is a view of the tool as it appears in plan when mounted in a boring bar for use, the work being fragmentarily illustrated. I

Fig. 6 is a view in perspective of a modified embodiment of the instrument per se.

Like parts are identified by the same reference characters throughout the several views.

The tool I is mounted for use in a boring bar 8.

' The particular mounting may be in accordance with the disclosure of the Hassig Patent 2,227,084 of December 31, 1940. In different boring bars and the like, the tool may project at different angles. That is to say, the axis CD of the tool may have any desired angular position with respect to the axisupon which the boring basil is rotated respecting the work.

Whatever the angular position of the center line CD of the tool, it is necessary to provide for predetermined back rake and side rake. The tool is so shaped as to provide cutting edges at 9 and Hi. Grinding is done upon the surface l2 which is bounded by the margins 9 and III at which cutting occurs. In order that the surface l2 may slope at a desired angle with respect to its path of movement through the work, the surface I 2 may be so ground as to be inclined in two directions from aposition at right angles to its path of movement. Its back rake, as measured in the plane indicated by the line WX in Fig. 5,

may, for example, be of the order of 10 degrees behind a plane determined by the axis of the boring bar and the radius drawn from such axis to the cutting edge 9." The side rake, as measured along the line YZ in Fig. 5, may, for example, range anywhere from 3 degrees to 10 degrees backwardly from the plane determined by the axis of the boring bar and the edge ll] of the tool. The figures given are purely illustrative. or no angle may be desired.

For grinding, the tool I is removed from the boring bar 8 or other carrier and positioned in the fixture block I5. The fixture block has a wedge clamp l6 similar to that provided in the tool carrier, the clamping member I6 being drawn by clamping screw I'l into engagement with the flat side l8 of the tool so that the tool is held in a well defined position in the fixture block l5.

Fixture block I 5 is now mounted in a so-called Any angle universal vise which has a base l9, and a tiltabla table pivotally adjustable with respect to the base and adapted to be secured in adjustment by a clamp nut 2|. The vise table 26 carries a stationary clamp jaw 22 and a movable clamp jaw 23 adjustable by means of the vise screw 24. The fixture block |5 is clamped between the jaws 22 and 23 to hold the tool I in a position where the surface |2 thereof can be exposed for grinding. The base I9 is then mounted on the table of a surface grinder for translative movement with respect to the grinding wheel 26, it being obvious that although the grinder table is ordinarily the part which travels, the wheel might have translative movement so far as this invention is concerned.

While the vise itself is not per se universal, having but a single axis of adjustment, it provides for universal adjustment of the block IS in which the tool is mounted for grinding. The base l9 may be set at any desired position on the grinder table 25, thus giving adjustment on one axis. The vise table 20 is pivotal on the axis of clamp 2| with respect to the vise base Hi to provide for a second axis of adjustment, and the fixture block i5 may be adjusted between the jaws 22 and 23 to provide for a third axis of adjustment. Since the vise base l9 will ordinarily be located in parallelism with the path of relative movement of the grinding wheel and the grinder table,-the present invention is primarily concerned with adjustmenteifective about the axis of the vise clamp 2| and pivotal adjustment at right angles thereto in the plane determined by the opposing faces of the vise jaws 22 and 23.

Because the tool 7, as mounted in the fixture block IS in the vise, does not have the same angle at which the tool is located in its boring bar or other carrier (and because the latter angle varies widely in different equipment) it is necessary to provide some means for determining back rake and side rake with due regard to the angle at which the tool is actually used. For the purposes of the preferred instrument shown in Fig. 1, I provide my fixture block i5 with a pair of spaced parallel guide rails 27 and 28 projecting upwardly from its upper surface 29.

My improved instrument has a base 30 which is made to fit accurately between the rails 27 and 28 to assure parallelism of the base with the axis of tool 1 when the instrument is mounted on the fixture block l5.

Swiveled in the base 30 is an upstanding post 3| which is preferably exactly normal to the base 30. The base 30 may be slotted at 32 and provided with a tension screw 33 for clamping the base with any desired degree of pressure upon the post 3| to determine the frictional resistance to the rotation of the post, whereby the post tends to remain in any position to which it is adjusted. The post may carry a dial at 3 4 and the base may be provided with a ca1i 'brated scale at cooperating with the dial to indicate the particular angle of rotative adjustment of the post 3| respecting the base.

At the upper end of post 3| is a head as from which a pair of brackets 4| and 42 project at right angles. Pivoted to these brackets are arms 43 and 44 respectively. Clamping nuts 45 and 46 upon the pivot bolts hold the arms releasably in any position to which they are manually adjustable. Each arm is provided with a mark at 4'! which serves as a ointer. The pointer of arm 43 moves across a calibrated scale at 48, while the pointer portion of arm 44 moves across a calibrated scale 49. The scales 48 and 49 are calibrated prefenably in degrees, although arbitrary calibrations may be employed. While difierent arrangements are possible, within the contemplation of this invention, the particular organization disclosed, in which both arms are pivoted at their outer ends to the respective brackets, is such that both scales read upwardly in a positive direction.

Each of the respective arms 43 and 4 4 is provided with a spirit level at 50.

The instrument is used in the following manner.

First, the dial 34 carried by the post 3| is rotated with respect to the calibrated scale 35 on the base to set the post at the exact angle between the position at which the tool axis is supported in the fixture for grinding and the position which the tool axis occupies when the tool is mounted in its boring bar or other carrier for use. In the device illustrated, that angle is approximately 40 degrees.

Secondly, the pivoted arm 43 is adjusted with respect to its scale 48 to the exact back rake angle desired, such angle being shown by the graduations or calibrations of the scale 48. Then the arm 44 is adjusted with respect to its scale 30 49 tothe exact side rake angle desired, such angle being indicated by the calibrations of scale 49.

With the instrument positioned on the fixture block I5 between the guides 21 and 28, and the jaw 23 and the clamping nut 2| sufficiently loose to permit the block to be manipulated, the block, already containing the tool to be ground, is raised and lowered about the axis of the clamping nut 2| and is tilted about the right angle axis defined "by the parallel surfaces of jaws 22 and 23 until the bubbles of the spirit levels 50 in both of the arms 43 and 44 show that the block is positioned in the proper plane for grinding. When such a position is reached the bubbles in the spirit glasses will be centered in the glasses. The clamps are now tightened and, if desired, the instrument may be removed from the fixture block and the grinder is operated to cause the wheel 26 to traverse the face I2, thereby grinding such face to exactly the desired plane.

It will be noted that the arms 43 and 44 are not adjustable in the same planes in which the block l5 and. the tool are adjusted in the vise. Nevertheless, the planes in which the arms 43 and 44 have their pivotal movement are, preferably, at least, the identical planes in'vvhich the angles of back rake and side rake are measured. The fact that the adjustments of the tool in the vise are efiected in totally different planes complicates the problem but is requisite to enable standard vise and grinding equipment to be used. It is because of this discrepancy between the plane of adjustment and the plane of measurement that great difficulty has heretofore been experienced. However, by manipulating all adjustments concurrently (as is possible where it is only necessary to read the level as distinguished from taking an actual measurement in degrees) the exact plane of desired grinding is very readily established regardless of the directions in which the adjustments are effected.

The method may be practiced irrespective of any particular tool by setting spirit levels at an angle (preferably a right angle) to each other thus tilted in fixed positions regarding the work face to be ground, it will be apparent that when the levels are adjusted to horizontal, the work face will occupy the desired grinding plane.

' Atthe expense of some convenience, it is pos sible to simplify the instrument in the manner suggetsed in Fig. 6. In this construction the arms, 44. and theirmountings', are identical with those previously described. In this instance, however, a single unitary part 55 is flanged at 56 to provide a base and it has portions 51 and sible to adjust the whole body 55 of the instrument by means of a protractor upon the flatsur face of a fixture block in which the tool ismounted. In other words, the guide rails 21 and 28 would preferably be omitted from the fixture block i=5 if this type of instrument were to be used, and the body 55 would simply be set by protractor on the top of the block at the desired angle to locate the arms 43 and so that these would swing in the' planes in which the back rake and side rake should be measured. Naturally, it is preferred to use the Fig. l construction in which the'swiveling of the post 3| and the provision of the scale permit this angle to be determined without any separate protractor or other accessory tool.

I believe that those skilled in the art will readily appreciate that avariety. of changes may be made in the specific instrument herein disclosed without departing from the concept as above outlined.

I claim:

1. A setting guide for tool holders, comprising a base adapted to be mounted upon a tool holder in a predetermined relation to a tool carried thereby, an upright post swiveled in'said base for rotative adjustment about is own axis, bracket will determine the'position of said bracket means with reference to'a horizontal plane, said-bracket means being mountable upon a tool holder, with said faces extending at equal angles to the axis of a tool carried by the holder.

' 4. 'In' to'ol'grinding equipment, the combination with a base having a swivel clamp, of an upright post swiveled in said'clamp, said post and base having coacting calibrations indicating the angle of position ofthepost, bracket members carried by the post above the base and angularly related to each other, pivot bolts carried by the bracket heads at points remote from the post; arms mountedon. said pivot bolts and having free end portions projecting therefrom toward the post, clamp means for fixing the angular adjustment of the respective arms upon their respective bolts, and means providing anindicating'scale showing the angular adjustments of the respective arms, each of said arms being provided with aspirit level, and means for mounting a tool in fixed relation to said base and adjusting the base to a position in a grinding place with each of said arms in a level position. I

5. The combination with a fixture adapted to hold a tool for grinding of a base keyed to the fixture in a predetermined position with reference to a tool thereon, bracket means comprising angularly related divergent arms mounted on said base, saidarms being adjustable about an axis perpendicular to the base, lever arms pivotally adjustable in upright angularly related planes with respect to the bracket arms, said bracket means mounted on said post, arms pivoted to said bracket means for adjustment in angularly related planes which are upright respecting said base, and level indicating devices carried by the respective arms whereby to define when level a predetermined plane for said base.

2. A setting guide for tool holders, comprising the combination with bracket means of angular form, of arms mounted for pivotal adjustment at remote points on said bracket means and projecting toward a common apex, calibrated scale arms and lever arms having ccacting calibrated 7 scale meansfor indicating the angularpositions in such planes of the respective lever arms,- and level means carried by the respective lever arms where-by to facilitate adjusting the tool with one of its faces in a grindin plane tilted in two directions from a horizontal plane.

6. The device set forth in claim 5, in which said bracket arms are at right angles to each other and are positively pivoted for pivotal movement with respect to the fixture about an axis at right angles to both of said arms.

- mined position with reference to said base, brackmeans with-respect to which the free ends of said arms are pivotally adjustable, level means carried by the respective arms, and means for mounting said guide on a tool holder with said arms extending at predetermined angles to the axis of a tool carried by the holder.

3. A setting guide for tool holders, comprising bracket means having faces joined approximately at right angles, in combination with arms pivoted to the bracket means at points remote from the juncture of said faces and having free end portions extending toward such juncture, clamp means for maintaining the arms in predetermined pivotal adjustment upon their respective faces, said arms and faces having interacting gauge means for indicating the respective positions of said arms, and spirit levels carried by the respective arms whereby the leveling of said arms in predetermined positions of angular adjustment et means providing a pair ofdivergent arms, means pivoting the bracket means to the base for adjustment upon an axis extending away from said fixture, a pair of lever arms pivoted to the bracket arms at points remote from said axis and projecting toward said axis, levels carried by the respective lever arms, and means for positioning the lever arms at predetermined angles in their pivotal adjustment respecting the bracket arms, the adjustment of the bracket arms to a particular angular position about the first mentioned axis, and the adjustment of the lever arms to predetermined angular positions of pivotal adjustment with reference to their respective bracket arms, followed by the leveling of both of the lever arms being adapted to establish a predetermined position for a tool mounted in said fixture.

8. An instrument for setting a tool with one of its faces in a grinding plane comprising the combination with a tool holder having a tool receiving socket and a supporting surface'in a predetermined position with reference to said socket of an angle. bracket flanged to comprise a base, pivotv posts projecting; from angularly related portions of said bracket, lever pivoted to said posts, and spirit levels mounted on said le vers, said bracket being adjustable on they tool holder to a position with said levers extending at equal angles to a plane which includes the axis of the tool receiving socket.

9. Tool grinding equipment, inclding the combination of a tool holder provided with means for Securing a tool in fixed relation to a grinding plane, a setting guide for the tool holder, a pair of supports thereon adapted for independent swinging adjustments in divergent planes, calibrating means associated with each support for indicating its pitch with reference to a horizontal plane, a tubular level carried by each support, means for mounting the setting guide on the tool holder with its levels extending in planes at predetermined angleS to the axial line of the tool, and means for adjusting the tool holder to bring both levels to a horizontal position.

10. Tool grinding equipment, including the combination with a tool holder provided with means for rigidly securing a tool thereto, of means to predetermine the pitch of the tool surface to be ground, including a setting guide provided with a pair of calibrated pitch indicators extending in planes oppositely divergent from a common apex, said guide being mountable on the tool holder with such apex in a plane which coincides with the axis of the tool, and means for adjusting the tool holder to bring said surface of the tool to a pitch in correspondence with that. predetermined by the pitch indicators, and level indicating means associated with the pitch indicators, whereby the proper adjustment of the tool holder may be visually determined.

11. In a tool g indingapp atus, th com ination with a, tool holder provided with means for rigidly securing a tool thereto with one, of

' its surfaces in fixed relation to a grindin urportsv to a predetermined pitch with reference to the base of the setting guide, and means for adjusting the tool holder to bring said supports to a position in which the levels indicate a horizontal plane.

12. In a tool grinding apparatus, the combination with a tool holder provided with means for rigidly securing a tool thereto with one of its surfaces in fixed relation to a grinding surface, said tool holder being provided with a mounting fora setting guide, a setting guide having a base adapted to fit said mounting, calibrated pitch indicators carried by the setting guide and ad justable in planes divergent in opposite directions from the axis of a tool secured to the holder as aforesaid, means for adjusting the tool holder to a position in which the tool face to be ground is pitched from a horizontal plane in the directions determined by the pitch indicators, and level indicating means associated with the pitch indicators, whereby the proper adjustments of the tool holder may be visually determined.

WILLARD J. CLEMENTS. 

